Apparatus for the conjoint gripping of bobbins on a ring spinning or ring-twisting machine

Abstract

An apparatus for the conjoint gripping of bobbins by means of pins or spigots formed of a rigid material, mounted at a support or carrier, and insertable into the bobbins. An expansible hose or tube member extends lengthwise of the support, this hose member when subjected to an increased internal pressure serving to press the bobbins against the pins or pin members inserted therein. This known apparatus has the advantage that there does not occur damage to the entering pin members, nor does there arise permanent deformation or destruction thereof. Yet, such apparatus possesses the shortcomings that the seized bobbins, when pressed against the pin members, are not positioned with sufficient accuracy in a direction parallel to the longitudinal direction of the support. The invention avoids such drawback in that, there are provided two straight edges at each pin member at the side thereof confronting the hose member, such too straight edges extending in the longitudinal direction of the related pin member and serving as contact surfaces for the bobbin pressed thereagainst.

What I claim is: 
     
       1. An apparatus for the conjoint gripping of empty or wound bobbins on a textile machine, especially ring-spinning or ring-twisting machines, comprising: pin members formed of a rigid material and insertable into the bobbins which are to be gripped;   a support member extending along the textile machine;   said pin members being carried by said support member;   an expansible hose member extending along said support member, wherein the internal pressure of said expansible hose member can be varied;   said expansible hose member extending in the direction of the bobbins for pressing the bobbins against the pin members inserted therein when the internal pressure of the expansible hose member is increased;   each pin member having a side surface at a side thereof facing the hose member;   said side surface being bounded by two substantially straight edges extending in the lengthwise direction of its pin member; and   said substantially straight edges serving as abutment means for an internal surface of the related bobbin when such bobbin is pressed against the pin member.   
     
     
       2. The apparatus as defined in claim 1, wherein: each pin member possesses a substantially prismatic shape; and   each of the side surfaces of said pin members which contain said two substantially straight edges being located in a plane extending substantially parallel to the longitudinal direction of said support member.   
     
     
       3. The apparatus as defined in claim 2, wherein: each of said edges extending in the lengthwise direction of the pin member is provided with grooves formed by a turning machining operation.   
     
     
       4. The apparatus as defined in claim 1, wherein: each pin member has a substantially quadrangular cross-sectional configuration.   
     
     
       5. The apparatus as defined in claim 1, wherein: said two straight edges are structured such that they possess a relatively large gripping capability with an inner surface of the bobbin gripped by the pin member.   
     
     
       6. The apparatus as defined in claim 5, wherein: the two edges are structured to possess grooves running transversely with respect to said two edges in order to increase said gripping capability of said two edges.   
     
     
       7. The apparatus as defined in claim 1, wherein: said two edges are interrupted in the lengthwise direction of extent thereof.